WO2014083698A1

WO2014083698A1 - Ablation catheter

Info

Publication number: WO2014083698A1
Application number: PCT/JP2012/081168
Authority: WO
Inventors: 義昭長嶋; 内山　靖二郎; 達道藤原
Original assignee: 株式会社グツドマン
Priority date: 2012-11-30
Filing date: 2012-11-30
Publication date: 2014-06-05
Also published as: JPWO2014083698A1; JP6059737B2

Abstract

The purpose of the present invention is to provide an ablation catheter which comprises electrode wires, wherein the easiness of insertion of the ablation catheter is enhanced and a temperature detection wire can be installed with reduced man-hours. A balloon catheter (10) is provided with a catheter tube (11) and a balloon (13) which is provided on the distal end side of the catheter tube (11). Electrode wires (20) are provided on the outer peripheral surface of the balloon (13). An annular member (22) is provided on the outer peripheral surface of an outer tube (15) at a position closer to the proximal end side than the balloon (13) so as to surround the outer peripheral surface of the outer tube (15). The electrode wires (20) are individually joined to the outer peripheral surface of the annular member (22). The hot junction (27a) of a thermocouple (27) is provided on the inner peripheral surface side of the annular member (22).

Description

Ablation catheter

The present invention relates to an ablation catheter.

In recent years, ablation catheters have been used in the treatment of cardiac arrhythmias and hypertension. The ablation catheter includes an electrode on the distal end side of the catheter. In an ablation catheter, this electrode is provided in close contact with a lesion site such as an arrhythmia source, and the lesion site is burned by energizing the electrode with high frequency in this state. In the treatment of hypertension, as in the case of ablation for cardiac arrhythmia, energization with high frequency is performed in the renal artery, thereby performing renal sympathetic denervation (Renak denervation) running around the renal artery in a mesh manner.

Patent Document 1 discloses an ablation catheter using a balloon catheter. In the catheter of Patent Document 1, a plurality of electrode wires are provided on the outer surface of the balloon so as to extend in the axial direction, and by inflating the balloon, each electrode wire is brought into close contact with the lesion site to cause burning. It has become a thing.

Special table 2010-507404 gazette

By the way, when incinerating the ablation site using an ablation catheter, the incineration is performed while controlling the temperature around the ablation site (incineration temperature) in order to incinerate at an appropriate temperature. In performing this control, a temperature sensor for detecting the temperature around the ablation site is required, and for example, a thermocouple is used as the temperature sensor in this case.

It is conceivable that such a thermocouple is provided, for example, with respect to an electrode wire arranged at a fuel part. Here, when providing a thermocouple in the catheter of the said patent document 1 which has a some electrode wire, it is possible to provide a thermocouple for every electrode wire, respectively. However, in this case, since there are a plurality of thermocouples, the outer diameter of the catheter is increased correspondingly, and there is a possibility that the insertion property of the catheter is reduced. Also, the work of providing a thermocouple for each electrode wire is laborious and may increase the number of work steps.

A main object of the present invention is to provide an ablation catheter capable of improving the insertion property and reducing the number of work steps when providing a temperature detection line in a configuration including a plurality of electrode wires. To do.

In order to solve the above problems, an ablation catheter of the first invention includes a tubular catheter body and a plurality of electrode wires provided on the outer peripheral side of the catheter body on the distal end side of the catheter body. The ablation catheter includes a heat transfer body to which each of the electrode wires is connected, and a temperature detection line that is provided on the heat transfer body and has a temperature detection unit that detects the temperature of the heat transfer body. And

According to the ablation catheter of the present invention, a plurality of electrode wires provided on the outer peripheral side of the catheter body are connected to the heat transfer body, and a temperature detection portion of the temperature detection line is provided for the heat transfer body. ing. In this case, when ablation (cauterization) is performed, if the ablation site is heated by energizing the electrode wire, the heat of the ablation site is transferred to the heat transfer body via the electrode wire, and the temperature of the heat transfer body is detected by temperature detection. Detected by the part. In this case, since the temperature of the ablation site can be indirectly detected via the electrode wire and the heat transfer body, the temperature control of the ablation site can be performed based on the detected temperature.

In the present invention, since the temperature of the heat transfer body is detected by the temperature detection line, one temperature detection line can be shared for a plurality of electrode lines. Therefore, for example, only one temperature detection line needs to be provided, and the number of temperature detection lines can be reduced as compared with the case where a temperature detection line is provided for each electrode line. As a result, the outer diameter of the catheter can be reduced by that amount, so that the insertion property can be improved, and the number of work steps for providing the temperature detection line can be reduced.

The ablation catheter of the second invention is characterized in that, in the first invention, the heat transfer body is provided along the outer peripheral surface so as to surround the outer peripheral surface of the catheter body.

According to the present invention, since the heat transfer body is provided so as to surround the outer peripheral surface of the catheter body, it is possible to secure a wide area in the heat transfer body where the electrode wires can be connected in the catheter outer peripheral direction. Thereby, in the structure by which the several electrode wire is arrange | positioned by the predetermined | prescribed space | interval in the catheter outer peripheral direction, these several electrode wires can be connected suitably to a heat exchanger.

The ablation catheter according to a third aspect of the present invention is the ablation catheter according to the second aspect, wherein the plurality of electrode wires are connected to either the inner peripheral surface side or the outer peripheral surface side of the heat transfer body, and the other side is A temperature detector is provided.

Since a plurality of electrode wires are connected to one of the inner peripheral surface side and the outer peripheral surface side of the heat transfer body and the temperature detection section is provided on the other side, the temperature detection section is arranged on the heat transfer body. It can suppress that an electrode wire becomes obstructive. Thereby, the operation | work which provides a temperature detection part in a heat exchanger can be made easy.

An ablation catheter according to a fourth invention is the ablation catheter according to the third invention, wherein the heat transfer body is made of metal, the temperature detection line is a thermocouple, and a hot junction as the temperature detection unit in the thermocouple is provided. The heat transfer body is provided on the other side of the heat transfer body with an insulating layer interposed between the heat transfer body and the heat transfer body.

Incidentally, it is conceivable that a thermocouple having a relatively low cost and excellent thermal response is used as the temperature detection wire. Since thermocouples detect temperature based on the voltage difference generated between the joints of two different types of metal wires, when using a thermocouple, the hot junction is made of a metal that is the object of temperature detection. It is necessary to provide the heat transfer body in a state of being electrically insulated. Therefore, in the present invention, in view of this point, the hot junction of the thermocouple is provided in a state where an insulating layer is interposed with respect to the heat transfer body. Thereby, the temperature of the heat transfer body can be suitably detected without being affected by the power flowing from the electrode wire to the heat transfer body.

Further, in this configuration, since a plurality of electrode wires are arranged on one side of the inner peripheral surface side and the outer peripheral surface side of the heat transfer body and a thermocouple is arranged on the other side, an electrode for the heat transfer body It can be avoided that the connecting portion of the wire is narrowed by the insulating layer, and as a result, the connecting operation of the electrode wire can be facilitated.

The ablation catheter of the fifth invention is characterized in that, in any of the second to fourth inventions, the plurality of electrode wires are connected to the outer peripheral surface of the heat transfer body.

According to the present invention, since the plurality of electrode wires are connected to the outer peripheral surface of the heat transfer body, the electrode wires are transmitted as compared with the configuration in which the plurality of electrode wires are connected to the inner peripheral surface of the heat transfer body. The operation of connecting to the heat body can be facilitated.

The ablation catheter according to a sixth aspect of the present invention is the invention according to any one of the second to fifth aspects, wherein the temperature detection unit is sandwiched between the inner peripheral surface of the heat transfer body and the outer peripheral surface of the catheter body. Is provided.

According to the present invention, since the temperature detection unit is provided between the inner peripheral surface of the heat transfer body and the outer peripheral surface of the catheter body, the temperature detection unit can be easily adhered to the heat transfer body side, It becomes possible to detect the temperature of a heat exchanger suitably.

An ablation catheter according to a seventh invention is the ablation catheter according to the sixth invention, wherein the heat transfer body is made of metal, the temperature detection line is composed of a thermocouple, and the hot junction as the temperature detection unit in the thermocouple is The outer peripheral surface of the catheter main body is provided in a state of being covered from the outside by an insulating material, and the heat transfer body is disposed outside the insulating material so that the hot junction contacts the heat transfer body. It is sandwiched between the catheter body.

According to the present invention, the hot junction of the thermocouple is provided on the outer peripheral surface of the catheter body while being covered from the outside by the insulating material, and the metal heat transfer body is disposed outside the insulating material. Therefore, an insulating material is interposed between the hot junction and the heat transfer body. Thereby, the temperature of the heat transfer body can be suitably detected by the hot junction without being affected by the electric power flowing from the electrode wire to the heat transfer body.

In addition, since the hot junction is sandwiched between the heat transfer body and the catheter body, it is easy to make the hot contact close to the heat transfer body side (specifically, an insulating material), and therefore, between the hot contact and the heat transfer body. Even in the configuration in which the insulating material is interposed, the temperature of the heat transfer body can be suitably detected.

The ablation catheter according to an eighth aspect of the present invention is the ablation catheter according to any one of the first to seventh aspects, wherein the outer peripheral surface of the catheter body is covered with a cover tube so as to cover the heat transfer body from the outside. The cover tube and the catheter body are joined to each other to prevent blood from entering the heat transfer body.

According to the present invention, the cover tube is covered so as to cover the heat transfer body on the outer peripheral surface of the catheter main body, and blood enters the heat transfer body side by joining the cover tube and the catheter main body. Is prevented. Accordingly, it is possible to prevent blood from entering the heat transfer body and causing the heat transfer body to be cooled, so that the temperature of the heat transfer body can be suitably detected.

An ablation catheter according to a ninth aspect of the present invention is the ablation catheter according to any one of the first to eighth aspects, wherein the catheter body includes a balloon having an inflating portion that is inflated or deflated using a fluid on a distal end side thereof. The plurality of electrode wires are provided on the outer peripheral side of the balloon so as to straddle at least the expansion portion in the axial direction of the balloon, and the heat transfer body has an annular shape surrounding the outer peripheral surface of the catheter body. And provided on either side of the expansion portion in the axial direction and joined to one end portion of the plurality of electrode wires, and the heat transfer body accompanies expansion of the expansion portion. It is possible to operate following the displacement of the electrode wire, or an annular shape that surrounds the outer peripheral surface of the catheter body on the opposite side of the heat transfer body with the expansion portion interposed therebetween. When an annular member joined to each of the other end portions of the plurality of electrode wires is provided, the annular member can operate following the displacement of the electrode wire accompanying the expansion of the expansion portion. It is characterized by that.

According to the present invention, the heat transfer body can operate following the displacement of the electrode wire accompanying the expansion of the balloon, or an annular member joined to each of the other end portions of the plurality of electrode wires is provided. In this case, the annular member can operate following the displacement of the electrode wire accompanying the inflation of the balloon. In this case, since the load applied to the electrode wire can be absorbed when the electrode wire is displaced, an inconvenience that an excessive pulling force is applied to the electrode wire to break the electrode wire or inhibit the inflation of the balloon is suppressed. be able to.

An ablation catheter according to a tenth aspect of the present invention is the ablation catheter according to any one of the first to ninth aspects, wherein one end of each of the plurality of electrode wires is connected to the lead wire via the heat transfer body, and the other end also It is connected to a lead wire, and each of the plurality of electrode wires is supplied with electric power from a power supply device through each lead wire.

In the configuration in which power is supplied only from one end side to each electrode line, it is assumed that the voltage decreases in the electrode line from the one end side toward the other end side. It is assumed that the amount of heat generated from the one end side toward the other end side also decreases. If it becomes so, it will be difficult to cauterize at a uniform temperature in the whole electrode wire. In that respect, according to the present invention, since electric power is supplied from both ends of the electrode wire to the electrode wire through the lead wires, the amount of heat generated in the entire electrode wire can be easily made uniform, and the temperature can be made uniform in the entire electrode wire. It becomes possible.

1 is a schematic overall side view of a balloon catheter. It is a side view which shows the structure of a balloon and its periphery, (a) shows the inflated state of a balloon, (b) has shown the deflated state of the balloon. (A) is a longitudinal cross-sectional view which shows the structure of a balloon and its periphery, (b) is an enlarged view of the area | region C1 in (a), (c) is an enlarged view of the area | region C2 in (a). FIG. 4 is a cross-sectional view taken along line AA in FIG. Explanatory drawing for demonstrating the work procedure at the time of providing an electrode wire on a balloon. (A) is a side view showing a configuration of a balloon and its surroundings in another embodiment, and (b) is a cross-sectional view taken along line BB of (a). (A) is a side view which shows the structure of the balloon in other embodiment, and its periphery, (b) is an enlarged view of the area | region C3 in (a). The cross-sectional view which shows the electrode wire in other embodiment. The longitudinal cross-sectional view which shows the state which connected the lead wire to the cyclic | annular member in other embodiment.

Hereinafter, an embodiment embodying the present invention will be described with reference to the drawings. In this embodiment, the ablation catheter is embodied as a balloon catheter. FIG. 1 is a schematic overall side view of a balloon catheter 10.

As shown in FIG. 1, a balloon catheter 10 includes a catheter tube 11, a connector 12 attached to the proximal end (base end) of the catheter tube 11, and a distal end (tip end) of the catheter tube 11. ) Attached to the balloon 13.

The catheter tube 11 is composed of a plurality of tubes, and has an inner / outer multiple tube structure (inner / outer double tube structure) from at least an intermediate position in the axial direction to the position of the balloon 13. Specifically, the catheter tube 11 includes an outer tube 15 and an inner tube 16 having an inner diameter and an outer diameter smaller than the outer tube 15, and the inner tube 16 is inserted into the outer tube 15. The above multi-tube structure is used.

Both the outer tube 15 and the inner tube 16 are made of polyamide resin so as to have a predetermined flexibility. However, as long as it has flexibility, it is not limited to polyamide resin, and synthetic resin materials such as polyethylene resin, polypropylene resin, polyurethane resin, and polyimide resin can be used. An additive may be mixed with the base material using the synthetic resin materials described above. Further, the outer tube 15 and the inner tube 16 may be formed using different synthetic resin materials.

The inner tube 16 is provided to extend to the distal end side from the outer tube 15, and the balloon 13 is provided so as to cover the extended region from the outside.

The outer tube 15 is formed in a tubular shape having outer tube holes 15a (see FIG. 3) that are continuous over the entire axial direction and open at both ends. The outer tube hole 15a communicates with the inner space of the balloon 13, and functions as a fluid lumen through which a compressed fluid flows when the balloon 13 is inflated or deflated. The inner tube 16 is formed in a tubular shape having inner tube holes 16a (see FIG. 3) that are continuous over the entire axial direction and open at both ends.

In the present balloon catheter 10, the catheter tube 11 and the balloon 13 constitute a tubular catheter body.

Next, the configuration of the balloon 13 and its surroundings will be described in detail with reference to FIGS. 2A and 2B are side views showing the configuration of the balloon 13 and its surroundings. FIG. 2A shows the inflated state of the balloon 13 and FIG. 2B shows the deflated state of the balloon 13. 3A is a longitudinal sectional view showing the configuration of the balloon 13 and its surroundings, FIG. 3B is an enlarged view of a region C1 in FIG. 3A, and FIG. 3C is FIG. It is an enlarged view of the area | region C2 in a).

As shown in FIGS. 2 and 3, the balloon 13 is provided so as to cover the region of the inner tube 16 that extends more distally than the outer tube 15 from the outside, as described above. , The proximal end is joined to the distal end of the outer tube 15, and the distal end is joined to the distal end of the inner tube 16.

The balloon 13 is made of a thermoplastic polyamide elastomer. However, it is not limited to polyamide elastomer as long as it can expand and contract well with fluid supply and discharge, and other thermoplastic resins may be used, such as polyethylene, polyethylene terephthalate, polypropylene, polyurethane, Polyamide, polyimide, polyimide elastomer, silicon rubber, etc. can also be used. Moreover, the compound for exhibiting a desired function and another polymer may be added with respect to the said thermoplastic resin.

The balloon 13 has joint portions at both ends joined to the catheter tube 11 and an inflating portion between the joint portions. More specifically, the balloon 13 is tapered such that the proximal leg region 13a joined to the distal end of the outer tube 15 and the inner diameter and the outer diameter are continuously expanded toward the distal end side. The proximal cone region 13b having a shape, the straight tube region 13c having the same inner diameter and outer diameter throughout the length direction and forming the maximum outer diameter region of the balloon 13, and the inner and outer diameters toward the distal end side. The distal cone region 13d, which is tapered so that the diameter is continuously reduced, and the distal leg region 13e joined to the distal end side of the inner tube 16 are arranged in this order from the proximal side. Have. The joining of the outer tube 15 and the proximal leg region 13a and the joining of the inner tube 16 and the distal leg region 13e are both performed by thermal welding. However, these bondings are not necessarily performed by heat welding, and may be performed using an adhesive or the like.

Note that the proximal cone region 13b, the straight tube region 13c, and the distal cone region 13d constitute an inflating portion.

When the compressed fluid is supplied into the balloon 13 through the outer tube hole 15 a of the outer tube 15, the balloon 13 is in an inflated state, and a negative pressure is applied to the outer tube hole 15 a so that the compressed fluid is discharged from the balloon 13. When discharged, it is in a contracted state. As shown in FIG. 2B, the balloon 13 is formed in a plurality of wings (specifically, three wings) having a plurality of wings 26 in the circumferential direction. The inflation region of the balloon 13 is folded so that 26 is formed, and the plurality of wings 26 are wound around the inner tube 16 around the axis.

The electrode wire 20 is provided on the outer peripheral side of the balloon 13. In the present balloon catheter 10, ablation (cauterization) is performed by the electrode wire 20, and the configuration of the electrode wire 20 and its surroundings will be described below.

2 and 3, a plurality (specifically, three) of electrode wires 20 are provided on the outer peripheral side of the balloon 13. The electrode line 20 is made of a Pt—Ir line, and its length dimension is larger than the length dimension of the balloon 13 in the axial direction. Each electrode line 20 is provided on the outer peripheral surface of the balloon 13 so as to extend in the axial direction, and is disposed so as to straddle the balloon 13 in the axial direction.

The electrode lines 20 are arranged at predetermined intervals in the circumferential direction of the balloon 13, and more specifically, are arranged at equal intervals (120 ° intervals). Each electrode line 20 is provided in a one-to-one correspondence on each wing 26 of the balloon 13. When the balloon 13 is contracted, each electrode line 20 is folded at the corresponding wing 26. It goes into the inner part.

Each electrode wire 20 is connected to a lead wire 21 at its distal end and is connected to an annular member 22 at its proximal end. As shown in FIGS. 3B and 3C, the lead wire 21 is made of a stainless steel wire and is inserted into the inner tube hole 16 a of the inner tube 16. The lead wire 21 has its distal end led out from the inner tube hole 16a to the distal side, and the lead-out portion is joined to the distal end of each electrode wire 20 by soldering. In this case, the distal end portion of each electrode wire 20 and the distal end portion of the lead wire 21 are electrically connected via the soldering portion 24.

A tip tube 25 is provided at the distal end of the inner tube 16 so as to cover the soldering portion 24 from the outside. The tip tube 25 is formed of a heat-shrinkable tube made of a resin material, and is disposed at an extended portion of the inner tube 16 that extends to the distal end side of the balloon 13. The tip tube 25 is provided so as to cover the outer peripheral surface of the tube 16 including the electrode wire 20 extending along the outer peripheral surface of the inner tube 16, and is welded so that the tip opening is closed. Thereby, exposure of the soldering part 24 is prevented and it becomes possible to suppress the damage of the blood vessel at the time of inserting the catheter 10 in a body.

The proximal end of the lead wire 21 is connected to the high frequency power supply 30 (see FIG. 1). The high frequency power supply device 30 supplies high frequency power to the electrode wire 20 through the lead wire 21. The frequency of the high frequency power is, for example, in the range of 200 kHz to 1 MHz. When the high frequency power is supplied to the electrode wire 20 by the high frequency power supply device 30 in a state where the electrode wire 20 is in contact with the internal combustion target site, the combustion site is heated and the incineration site is burnt. More specifically, when high-frequency power is supplied from the high-frequency power supply device 30 to the electrode wire 20, energization is performed between the electrode wire 20 and the counter electrode plate 31 disposed outside the patient's body, and combustion is accompanied by the energization. The part is heated and cauterization of the part is performed. The counter electrode plate 31 is connected to the high frequency power supply device 30 via a lead wire 32.

Next, the structure of the annular member 22 and its periphery will be described with reference to FIG. 4 in addition to FIG. FIG. 4 is a cross-sectional view taken along the line AA in FIG.

As shown in FIGS. 3C and 4, the annular member 22 is formed in an annular shape (cylindrical shape) from stainless steel, and more specifically, an endless annular shape. The annular member 22 has an inner diameter slightly larger than the outer diameter of the outer tube 15, and is provided so as to surround the outer peripheral surface of the outer tube 15 on the proximal side of the balloon 13. Here, the annular member 22 corresponds to a heat transfer body.

The proximal end of each electrode wire 20 is joined to the outer peripheral surface of the annular member 22 by welding. The electrode wires 20 are arranged at a predetermined interval in the circumferential direction of the annular member 22, and specifically, are arranged at equal intervals (120 ° intervals). The proximal ends of the electrode wires 20 are arranged at substantially the same position in the axial direction of the annular member 22. In this case, when the fuel part is heated by energizing each electrode wire 20, the heat is transmitted to the annular member 22 through the electrode wire 20, and as a result, the temperature of the annular member 22 is equal to the temperature of the fuel part. The temperature is the same or substantially the same.

The electrode wire 20 is not necessarily joined to the annular member 22 by welding, and may be joined by other joining methods such as adhesion, soldering, and caulking.

A thermocouple 27 for detecting the temperature of the annular member 22 is provided on the inner peripheral surface side of the annular member 22. In the present embodiment, the temperature of the annular portion 22 is detected by the thermocouple 27 so as to indirectly detect the temperature of the combustion part. The thermocouple 27 is a sheathed thermocouple in which a strand is covered with a sheath, and an alumel chromel wire is used as the strand. As for the thermocouple 27, the strand is exposed in the front-end | tip part, The exposed part becomes the warm junction 27a. The warm contact point 27 a is disposed on the inner peripheral surface side of the annular member 22. Here, the thermocouple 27 corresponds to a temperature detection line, and the hot junction 27a corresponds to a temperature detection unit.

The thermocouple 27 extends proximally with the warm junction 27a as a distal end, and the proximal end is connected to the high frequency power supply 30 (see FIG. 1). When the temperature of the annular member 22 is detected by the hot junction 27 a, the detected temperature information is input to the high frequency power supply device 30. Then, the high frequency power supply device 30 supplies power to the electrode wire 20 with a frequency corresponding to the input temperature of the annular member 22 (in other words, the temperature of the combustion part). Thereby, it is possible to control the temperature of the combustion part to a predetermined temperature.

The hot junction 27 a of the thermocouple 27 is fixed to the outer peripheral surface of the outer tube 15 by an insulating tape 28 on the inner peripheral surface side of the annular member 22. The insulating tape 28 is made of an electrically insulating material, for example, polyimide. The hot junction 27 a is covered by the insulating tape 28 from the outside in a state where the hot junction 27 a is fixed by the insulating tape 28.

The annular member 22 is disposed outside the insulating tape 28, and the hot contact 27 a is sandwiched between the inner peripheral surface of the annular member 22 and the outer peripheral surface of the outer tube 15 in the disposed state. In this case, the hot junction 27a is in close contact with the inner peripheral surface side (specifically, the insulating tape 28) of the annular member 22, so that the temperature of the annular member 22 can be suitably detected.

Further, in the arrangement state of the annular member 22, an insulating tape 28 as an insulating material is interposed between the warm contact point 27 a and the annular member 22. Therefore, the annular member 22 and the hot junction 27a are electrically insulated. Thereby, the temperature of the annular member 22 can be suitably detected by the hot junction 27a without being affected by the electric power flowing from the electrode wire 20 to the annular member 22 side. In this case, an insulating layer is constituted by the insulating tape 28.

Here, the positional relationship of the warm contact point 27a with respect to the electrode wire 20 in the annular member 22 will be described. The warm contact point 27a is arranged on the inner peripheral surface side of the annular member 22 as described above, and the proximal end portion of each electrode wire 20 (In other words, the joining end portion) is disposed on the outer peripheral surface of the annular member 22. Further, the hot junction 27 a is disposed closer to the proximal side than the proximal end portion of each electrode line 20 in the axial direction of the annular member 22, and one of the electrode lines 20 in the circumferential direction of the annular member 22. The electrode wire 20 is disposed at the same position as the proximal end of the electrode wire 20. However, the positional relationship of the warm contact point 27a with respect to the electrode wire 20 is not necessarily limited thereto, and the warm contact point 27a is located at the same position as the proximal end portion of each electrode wire 20 in the axial direction of the annular member 22 or more than that. You may arrange | position to a distal side and may arrange | position to the proximal end part of each electrode line 20 in the circumferential direction of the annular member 22, and may arrange | position.

The outer tube 15 is covered with a cover tube 29 so as to cover the annular member 22 from the outside. The length of the cover tube 29 in the axial direction is longer than the length of the annular member 22 in the same direction, and is arranged so as to cover the entire annular member 22 from the outside. The cover tube 29 is formed of a heat-shrinkable tube made of a contracted material, and is joined to the outer peripheral surface of the outer tube 15 by heat welding in a state of covering the annular member 22.

More specifically, the cover tube 29 is welded to the outer tube 15 on both sides of the annular member 22 in the axial direction. On the proximal side of the annular member 22, the cover tube 29 is welded to the outer tube 15 with the thermocouple 27 disposed on the inner peripheral side thereof. In this case, the thermocouple 27 is embedded in the resin layer 29a of the cover tube 29, and the cover tube 29 and the outer tube 15 are joined in a liquid-tight state in the embedded state. On the other hand, on the distal side of the annular member 22, the cover tube 29 is welded to the outer tube 15 in a state where the electrode wires 20 are arranged on the inner peripheral side thereof. In this case, each electrode wire 20 is embedded in the resin layer 29a of the cover tube 29, and the cover tube 29 and the outer tube 15 are joined in a liquid-tight state in the embedded state. This prevents blood from entering the annular member 22 side through the space between the outer tube 15 and the cover tube 29 from either the proximal end side or the distal end side of the cover tube 29.

Note that the cover tube 29 is not necessarily bonded to the outer tube 15 by welding, and may be bonded using other bonding methods such as adhesion.

Further, the cover tube 29 is arranged such that the distal end portion thereof is close to the proximal end portion of the balloon 13 (specifically, the proximal leg region 13a). Each electrode wire 20 is led out from the inside of the cover tube 29 to the distal side through a gap (gap) between the distal end portion of the cover tube 29 and the proximal end portion of the proximal leg region 13a.

Next, an operation procedure for manufacturing the balloon catheter 10 will be described. Here, in particular, an operation procedure when the electrode wire 20 is provided on the balloon 13 will be described. FIG. 5 is an explanatory diagram for explaining the work procedure. This operation is performed after the catheter tube 11 and the balloon 13 are joined and the catheter body 35 is manufactured.

First, as shown in FIG. 5A, an operation of joining each electrode wire 20 to the outer peripheral surface of the annular member 22 by welding is performed. In this case, compared with the case where each electrode wire 20 is welded to the inner peripheral surface of the annular member 22, the welding can be easily performed.

Next, as shown in FIG. 5B, the hot junction 27a of the thermocouple 27 is fixed to the outer peripheral surface of the outer tube 15 with an insulating tape 28, and then, as shown in FIG. The joined annular member 22 is disposed on the outer peripheral side of the outer tube 15. In this case, the annular member 22 is disposed so as to cover the insulating tape 28 from the outside with the annular member 22. As a result, the hot junction 27 a of the thermocouple 27 is disposed between the inner peripheral surface of the annular member 22 and the outer peripheral surface of the outer tube 15. That is, in this case, the hot junction 27 a is disposed on the inner peripheral side of the annular member 22 at the same time as the annular member 22 is disposed.

Here, as described above, since each electrode wire 20 is joined to the outer peripheral surface of the annular member 22, in other words, in the above arrangement of the annular member 22, the hot junction 27 a is connected to the inner peripheral surface of the annular member 22. When being arranged on the side, the electrode wire 20 is unlikely to obstruct the work. Therefore, it is possible to provide the warm contact point 27a on the annular member 22 relatively easily.

Further, since the annular member 22 is provided with the thermocouple 27 in this way, it is only necessary to provide one thermocouple 27. Therefore, compared to the case where the thermocouple 27 is provided for each electrode wire 20, the thermocouple 27 is provided. It is possible to reduce the number of work steps for providing the pair 27.

Next, as shown in FIG. 5 (d), the outer tube 15 is covered with the cover tube 29 so as to cover the annular member 22 from the outside, and in this state, the cover tube 29 is thermally welded to the outer tube 15. Do work. Thereby, the cover tube 29 and the outer tube 15 are joined in a liquid-tight state on both sides of the annular member 22.

Next, as shown in FIG. 5 (e), the lead wire 21 is inserted into the inner tube hole 16 a of the inner tube 16, and the distal end portion of the lead wire 21 is soldered to the distal end portion of each electrode wire 20. To join. After that, as shown in FIG. 5 (f), the tip tube 25 is placed on the inner tube 16 so as to cover the soldered portion 24 formed by the soldering from the outside, and in this state, the tip tube 25 is attached to the inner tube 16. Join to the outer peripheral surface by thermal welding. As a result, the tip opening of the tip tube 25 is closed, and the soldering portion 24 is prevented from being exposed.

Thereafter, a series of operations is completed by performing operations such as joining the connector 12 to the catheter body 35 as a post-process.

Next, a method for using the balloon catheter 10 will be described. Here, a description will be given of a work procedure when performing ablation (cauterization) by energizing the electrode wire 20 with a lesion site (lesion tissue) serving as an arrhythmia generation source as a burning target.

First, a guiding catheter is inserted into a sheath introducer inserted into the blood vessel, and the distal end opening of the guiding catheter is introduced to the coronary artery entrance. Next, the balloon catheter 10 is inserted into the blood vessel while being pushed and pulled along the guide wire G, and the balloon 13 is placed at the lesion site. Here, as described above, in the present balloon catheter 10, the temperature of the annular member 22 is detected by the thermocouple 27, so that one thermocouple 27 is shared by the plurality of electrode wires 20. ing. In this case, only one thermocouple 27 is required, and the number of thermocouples 27 can be reduced as compared with the case where the thermocouple 27 is provided for each electrode wire 20. Therefore, the outer diameter of the balloon catheter 10 can be reduced correspondingly, and it is possible to improve the penetration when the balloon catheter 10 is introduced into the blood vessel.

Next, a compressed fluid is supplied to the balloon 13 from the connector 12 side through the outer tube hole 15a of the outer tube 15 using a pressurizer, and the balloon 13 is inflated. As a result, each electrode line 20 is pressed against the lesion site by the balloon 13 and is brought into close contact with the site.

Next, high frequency power is supplied to the electrode wire 20 by the high frequency power supply device 30 to cauterize the lesion site (burning site). At this time, the high-frequency power supply device 30 controls the frequency of the high-frequency power based on the temperature of the annular member 22 detected by the thermocouple 27 and, consequently, the temperature of the lesion site heated by the flame. Thereby, cauterization can be performed while controlling the temperature of the lesion site to a predetermined temperature.

The high-frequency power supply device 30 and the like are provided with a temperature display unit that displays the temperature of the annular member 22 detected by the thermocouple 27, and the temperature display unit confirms the temperature of the annular member 22 (and thus the temperature of the lesion site). However, the frequency of the high frequency power may be manually adjusted.

After the cauterization of the lesion site is completed, the compressed fluid in the balloon 13 is discharged and the balloon 13 is deflated. Then, the balloon catheter 10 is extracted along the guide wire G from the blood vessel in the contracted state.

The balloon catheter 10 is mainly passed through a blood vessel as described above and used for treating blood vessels such as coronary arteries, femoral arteries, and pulmonary arteries. It can also be applied to “tubes” and “body cavities”.

As described above, according to the configuration of this embodiment described in detail, the following excellent effects can be obtained.

Since the hot contact 27 a of the thermocouple 27 is provided on the inner peripheral surface side of the metal annular member 22 and the insulating tape 28 is interposed between the hot contact 27 a and the annular member 22, the electrode wire 20 to the annular member 22. The temperature of the annular member 22 can be suitably detected by the thermocouple 27 without being affected by the flowing power. Further, in this configuration, since each electrode wire 20 is joined to the outer peripheral surface of the annular member 22, it is possible to avoid the joint portion of the electrode wire 20 with respect to the annular member 22 from being narrowed by the insulating tape 28, and as a result. The joining operation of the electrode wire 20 can be facilitated.

Moreover, since the warm contact point 27a is provided between the inner peripheral surface of the annular member 22 and the outer peripheral surface of the outer tube 15, the warm contact point 27a is easily brought into close contact with the annular member 22 side. For this reason, even if it is the structure which interposed the insulating tape 28 between the warm junction 27a and the annular member 22, the temperature of the annular member 22 can be detected suitably.

The outer tube 15 is covered with a cover tube 29 so as to cover the annular member 22 from the outside, and the cover tube 29 and the outer tube 15 are joined to each other, thereby preventing blood from entering the annular member 22 side. . Thereby, it is possible to prevent blood from entering the annular member 22 side and cooling the annular member 22, and the temperature of the annular member 22 can be suitably detected.

In the configuration in which the annular member 22 is provided on the outer peripheral side of the catheter body, since the annular member 22 is disposed on the proximal side of the inflating portion of the balloon 13, the annular member 22 is disposed on the distal side of the inflating portion of the balloon 13. Compared to the case, it is possible to suppress a decrease in penetrability.

The present invention is not limited to the above embodiment, and may be implemented as follows, for example.

(1) A modification of the ablation catheter (balloon catheter) is shown in FIG. 6A is a side view showing the configuration of the balloon and its surroundings, and FIG. 6B is a cross-sectional view taken along line BB of FIG. 6A.

As shown in FIGS. 6A and 6B, in the balloon catheter 60 of this example, a plurality (specifically, two) of electrode wires 61 are spirally formed along the axial direction on the outer peripheral surface of the balloon 13. Is provided. These electrode lines 61 are arranged at a predetermined interval in the circumferential direction of the balloon 13, and specifically, are arranged at equal intervals (180 ° intervals). Each electrode wire 61 has a distal end connected to the lead wire 21 and a proximal end fixed to the outer peripheral surface of the outer tube 15 on the proximal side of the balloon 13. Specifically, the proximal end portion of the electrode wire 61 is covered with the cover tube 62 from the outside on the outer peripheral surface of the outer tube 15, and the cover tube 62 is thermally welded to the outer tube 15. 15 and 62 are fixed.

The outer peripheral surface of the balloon 13, more specifically, on the outer peripheral surface of the straight tube region 13c, a heat transfer body 63 made of a metal material such as stainless steel is provided. The heat transfer body 63 has an annular shape surrounding the straight tube region 13c, and is formed by evaporating a metal material on the outer peripheral surface of the straight tube region 13c. Further, the heat transfer body 63 is disposed at a substantially central position in the axial direction in the straight pipe region 13c.

Each electrode wire 61 is joined to the outer peripheral surface of the heat transfer body 63. Each electrode wire 61 is joined to the outer peripheral surface of the heat transfer body 63 at the center in the length direction. Further, the electrode wires 61 are arranged at a predetermined interval in the circumferential direction of the heat transfer body 63, and specifically, are arranged at equal intervals (180 ° intervals). In addition, as a method of joining the electrode wire 61 to the heat transfer body 63, methods such as welding, soldering, adhesion, and caulking can be cited.

A hot junction 65 a of the thermocouple 65 is provided on the inner peripheral side of the heat transfer body 63. The hot junction 65a is provided inside the balloon 13, and is joined to the inner peripheral surface of the straight pipe region 13c by adhesion or the like. The hot junction 65 a is disposed at an intermediate position of each electrode line 61 in the circumferential direction of the heat transfer body 63, and specifically, is disposed at a central position of each electrode line 61. In this example, the thermocouple 65 is inserted through the outer tube hole 15 a of the outer tube 15.

Even in such a configuration, when the fuel part is heated by energizing the electrode wire 61, the heat is transmitted to the heat transfer body 63 via the electrode wire 61, and the temperature of the heat transfer body 63 is changed by the hot junction 65a. Detected. Therefore, the temperature of the incineration site can be detected indirectly, and the temperature control of the incineration site based on the detected temperature becomes possible. And by setting it as the structure which detects the temperature of the heat exchanger 63 in this way, the number of the thermocouples 65 can be decreased compared with the structure which provides the thermocouple 65 for every electrode wire 61. FIG. Thereby, the outer diameter of the balloon catheter 60 can be reduced correspondingly, and the insertion property can be improved. Further, by reducing the number of thermocouples 65, the number of thermocouples 65 inserted into the outer tube hole 15a (fluid lumen) of the outer tube 15 can be reduced, so that the thermocouple 65 is connected to the outer tube hole 15a. The thermocouple 65 can prevent the fluid flow in the outer tube hole 15a from being hindered.

Further, since the balloon 13 (specifically, the film thickness portion of the balloon 13) is interposed between the hot junction 65a and the heat transfer body 63, the balloon 13 can function as an insulating layer. Accordingly, it is possible to suitably detect the temperature of the heat transfer body 63 by the hot junction 65a without being affected by the electric power flowing from the electrode wire 61 to the heat transfer body 63. Moreover, since the warm contact point 65a is provided inside the balloon 13, it is possible to avoid the warm contact point 65a from coming into contact with blood. Thereby, it is possible to suppress erroneous detection of the temperature of the blood, and it is possible to accurately detect the temperature of the heat transfer body 63.

(2) In the above embodiment, the plurality of electrode wires 20 are joined to the outer peripheral surface of the annular member 22, and the thermocouple 27 (specifically, the hot junction 27 a) is provided on the inner peripheral surface side of the annular member 22. Conversely, a thermocouple 27 may be provided on the outer peripheral surface side of the annular member 22, and the plurality of electrode wires 20 may be joined to the inner peripheral surface of the annular member 22. Even in this case, it is possible to prevent the electrode wire 20 from interfering with the provision of the thermocouple 27 on the annular member 22, so that the operation of providing the thermocouple 27 on the annular member 22 can be facilitated.

Moreover, you may make it each provide the some electrode wire 20 and the thermocouple 27 in the outer peripheral surface side of the cyclic | annular member 22, and conversely to that, the some electrode wire 20 on the inner peripheral surface side of the cyclic | annular member 22 and A thermocouple 27 may be provided. Furthermore, some of the electrode wires 20 may be joined to the outer peripheral surface of the annular member 22, and the remaining electrode wires 20 may be joined to the inner peripheral surface of the annular member 22.

(3) In the above embodiment, the annular member 22 is disposed on the outer peripheral surface of the outer tube 15, but this is changed and the annular member 22 is disposed on the outer peripheral surface of the proximal leg region 13a of the balloon 13, or The outer leg 15a may be disposed across the outer circumferential surface of the proximal leg region 13a and the outer circumferential surface of the outer tube 15. In short, the arrangement position of the annular member 22 may be arbitrary as long as it is closer to the outer peripheral surface of the catheter body 35 than the inflation portion of the balloon 13.

Moreover, in the said embodiment, although the annular member 22 (heat-transfer body) was arrange | positioned more proximally than the balloon 13 (expansion part) in the outer peripheral surface of the outer side tube 15, it replaces with or adds to this, and an annular member The (heat transfer body) may be arranged on the distal side of the inflating part of the balloon 13. For example, it is conceivable to provide an annular member (corresponding to a heat transfer body) having an annular shape (cylindrical shape) at a portion of the inner tube 16 that extends further to the distal side than the balloon 13. In this case, the said annular member is provided so that the outer peripheral surface of the inner side tube 16 may be enclosed, and each electrode wire 20 and the lead wire 21 are each connected with respect to the said annular member. And the hot junction 27a of the thermocouple 27 is provided with respect to the said annular member. Also in this case, since the heat of the combustion part is transmitted to the annular member via the electrode wire 20 and the temperature of the annular member is detected by the thermocouple 27, the temperature of the combustion part is determined by the electrode wire 20 and the relevant part. It can be indirectly detected via an annular member.

Furthermore, as described in (1) above, a heat transfer body may be provided in the inflating portion of the balloon 13 (see FIG. 6).

(4) In the above-described embodiment, the annular member 22 (corresponding to a heat transfer body) is formed in an endless annular shape, but instead, the annular member may be formed in an endless annular shape such as a C-shaped cross section. . Further, the annular member 22 may be an elliptical ring instead of an annular ring.

Further, the heat transfer body is not necessarily formed in an annular shape, and for example, two heat transfer bodies having a semicircular (semi-arc) cross section may be provided so as to surround the outer peripheral surface of the outer tube 15. In this case, it is considered that a plurality of electrode wires are joined to each of the heat transfer bodies and a thermocouple (hot contact) is provided. Even in such a configuration, the number of thermocouples can be reduced as compared to the case where thermocouples are provided for each of the plurality of electrode wires, so that the outer diameter of the catheter can be reduced, and the insertion property can be improved. it can. In addition, the number of work steps can be reduced when performing the work of providing the thermocouple.

In this configuration, when fixing each heat transfer body, it is conceivable that the heat transfer body is fixed by being embedded in the outer tube 15 (specifically, its resin layer) in a state where each heat transfer body is partially exposed. .

(5) In the above embodiment, the lead wire 21 and the annular member 22 (heat transfer body) are made of stainless steel, but may be made of other metal materials such as copper, platinum, platinum-iridium, and brass. The annular member 22 is not necessarily formed of a metal material, and may be formed using other materials such as a resin material and a ceramic material as long as the material has excellent thermal conductivity. Furthermore, the annular member 22 may be formed integrally with the electrode wire 20. For example, it is conceivable that the annular member 22 and the electrode wire 20 are formed by cutting out from the same material (material).

Further, the lead wire 21 and the electrode wire 20 may be formed of the same metal material. In that case, the lead wire 21 and the electrode wire 20 may be integrally formed.

(6) In the above embodiment, the insulating tape 28 is affixed to the outer peripheral surface of the outer tube 15 so as to fix the hot junction 27a. However, the insulating tape 28 may be affixed to the inner peripheral surface of the annular member 22. Even in this case, since the insulating tape 28 can be interposed between the annular member 22 and the warm contact point 27a, the annular member 22 and the warm contact point 27a can be electrically insulated.

Further, the insulating layer (insulating material) is not necessarily formed by the insulating tape 28, and may be formed by a sheet material (insulating sheet) having electrical insulating properties, a tube material (insulating tube), or the like. When an insulating layer is formed by an insulating tube, the insulating tube may be provided on the hot junction 27a. Further, the hot contact 27a is fixed to the outer peripheral surface of the outer tube 15 with a sealing material or an adhesive excellent in electrical insulation without exposing the hot contact 27a to the outside, and an insulating layer is formed by the sealing material or the adhesive. May be.

(7) When the electrode wire 20 is displaced as the balloon 13 is inflated, it is assumed that an excessive load is applied to the electrode wire 20. In view of this point, a displacement absorbing structure that absorbs the displacement of the electrode wire 20 accompanying the inflation of the balloon 13 may be provided. FIG. 7 shows a specific example of this displacement absorbing structure. FIG. 7A is a side view showing the configuration of the balloon 13 and its surroundings, and FIG. 7B is an enlarged view of the region C3 in FIG.

As shown in FIGS. 7A and 7B, an annular member 40 to which the distal end portions of the electrode wires 20 are joined is provided on the distal side of the inflating portion of the balloon 13. The annular member 40 includes a resin layer 41 formed in an annular shape (cylindrical shape) and a metal coil spring 42 embedded in the resin layer 41. The resin layer 41 is provided in a portion of the inner tube 16 that extends further to the distal side than the balloon 13, and is joined to the outer peripheral surface of the portion by welding.

The coil spring 42 is embedded in the resin layer 41 with both end portions in the axial direction thereof being exposed from the resin layer 41. The proximal end portion 42a exposed to the proximal side in the coil spring 42 is joined to the distal end portion of each electrode wire 20 by welding, and the distal end portion 42b exposed to the distal side in the coil spring 42. Is joined to the distal end of the lead wire 21 by welding. In this case, each electrode wire 20 and the lead wire 21 are electrically connected via the coil spring 42. The electrode wires 20 and the lead wires 21 are not necessarily joined to the coil spring 42 by welding, and may be performed by other joining methods such as adhesion, soldering, and caulking. More specifically, a hole portion 45 penetrating the peripheral wall portion is formed in the peripheral wall portion of the inner tube 16, and the distal end portion of the lead wire 21 is drawn out from the inner tube hole 16 a through the hole portion 45. The distal end portion 42b of the coil spring 42 is joined.

In such a configuration, when the electrode wire 20 is displaced as the balloon 13 is inflated, the coil spring 42 is elastically deformed in the axial direction following the displacement. As a result, a load applied to the electrode wire 20 when the electrode wire 20 is displaced can be absorbed, so that an excessive tensile force is applied to the electrode wire 20 to cause the electrode wire 20 to break or to inhibit the balloon 13 from expanding. Inconvenience can be suppressed.

Further, instead of forming the annular member 40 including the coil spring 42, the annular member may be formed of a material such as rubber having elasticity. Even in that case, the annular member can be elastically deformed by following the displacement of the electrode wire 20.

(8) In the configuration of (7) above, the displacement absorbing structure of the electrode wire 20 is configured by elastically deforming the annular member. However, this is changed and the annular member is displaced by being provided so as to be movable in the axial direction. You may comprise an absorption structure. For example, instead of the annular member 40 in the configuration of FIG. 7, it is conceivable to provide an annular (cylindrical) metal annular member that is movable in the axial direction. Specifically, in this case, the annular member is provided in a state where it is not fixed to the outer peripheral side of the inner tube 16, so that the annular member can be moved along the axial direction of the inner tube 16. In such a configuration, when the electrode wire 20 is displaced as the balloon 13 is inflated, the annular member moves in the axial direction following the displacement, thereby absorbing the load applied to the electrode wire 20. Even when the annular member is movably provided as described above, a plurality of electrode wires 20 are joined to the outer peripheral surface of the annular member and the lead wire is connected to the inner peripheral surface, as in the case of the annular member 40 of FIG. 21 may be joined.

Here, since each electrode wire 20 is joined to the annular member movably provided and the coil spring 42 of FIG. 7, the annular member or coil spring 42 (hereinafter referred to as “movable”). The temperature contact point 27a of the thermocouple 27 may be provided to the movable annular member or the like, and the temperature of the movable annular member or the like may be detected by the warm contact point 27a. That is, the movable annular member or the like may be used as a heat transfer body.

(9) In the above embodiment, three electrode wires 20 are provided on the outer peripheral surface of the balloon 13, but two or four or more electrode wires 20 may be provided. The plurality of electrode wires 20 are not necessarily arranged at equal intervals in the circumferential direction of the balloon 13 and may be arranged at unequal intervals.

(10) In the above embodiment, Pt—Ir (platinum iridium alloy) is used as the material of the electrode wire 20, but other materials may be used. For example, it is possible to use materials such as gold, silver, platinum, and copper.

Further, as shown in FIG. 8, an electrode wire 50 having a core 51 made of Ni—Ti (nickel titanium alloy) and an outer layer 52 made of Pt (platinum) formed outside the core 51 is used. Also good. Ni—Ti is a superelastic alloy and has a shape restoring effect. For this reason, when the balloon 13 is deflated after the balloon 13 is inflated and the electrode wire 50 is in close contact with the lesion site, and then the balloon 13 is deflated, the electrode wire 50 is restored to its original shape (before the balloon 13 is inflated). It is easy to restore to (shape). Therefore, when the balloon 13 is pulled out of the body in a deflated state, it is possible to suppress the electrode wire 50 from being pulled out, and it is possible to suppress a decrease in operability during the pulling out. Further, since Ni—Ti is provided in the core 51, it is also preferable in terms of cauterization.

On the other hand, since Pt has a contrast function, the visibility of the electrode line 50 can be improved under X-ray projection. Thereby, the operation | work which arrange | positions the electrode wire 50 to a target lesion site | part can be made easy. In addition, since Pt is provided in the outer layer 52, an effect of enhancing contrast can be expected.

Note that, contrary to the example of FIG. 8, the core 51 may be formed of Pt and the outer layer 52 may be formed of Ni—Ti.

(11) In the above embodiment, the lead wire 21 is connected only to the distal end portions of the plurality of electrode wires 20, and power is supplied to the electrode wire 20 only from the distal end portions. 20, it is assumed that the voltage gradually decreases from the distal end side toward the proximal end side. Then, it is assumed that the amount of heat generated from the distal end side to the proximal end side in the electrode wire 20 is reduced, and it is difficult to cauterize the electrode wire 20 at a uniform temperature. It is done. In view of this point, for example, as shown in FIG. 9, the lead wire 55 is connected to the proximal end portion in addition to the distal end portions of the plurality of electrode wires 20, and the electrodes are connected through the

lead wires

21 and 55. You may make it supply electric power to the electrode wire 20 from the both ends of the wire 20, respectively. In the example of FIG. 9, one end of the lead wire 55 is connected to the high frequency power supply device 30 and the other end is joined to the outer peripheral surface of the annular member 22. In this case, the lead wire 55 (the other end thereof) is connected to the proximal ends of the plurality of electrode wires 20 via the annular member 22. According to this configuration, the amount of heat generated in the entire electrode wire 20 can be easily made uniform, and the temperature can be made uniform in the entire electrode wire 20.

(12) In the above embodiment, the thermocouple is used as the temperature detection line, but other temperature detection lines such as a resistance temperature detector may be used. For example, in the case of using a resistance temperature detector, a temperature detection part (sensor part) provided at the tip thereof is provided in contact with the annular member 22.

(13) In the above embodiment, the inflatable portion is configured by the balloon 13, but the inflatable portion may be configured by something other than a balloon, such as a stent or a net-like basket.

(14) In the above embodiment, the catheter tube 11 includes a plurality of outer tubes 15 having a fluid lumen (outer tube hole 15a) and inner tubes 16 having a lumen for inserting the lead wire 21 (inner tube hole 16a). Although it has a tube structure, it may be changed. For example, it is conceivable that the catheter tube is composed of a multi-lumen tube having a plurality of lumens, and any two of the plurality of lumens are used as a fluid lumen and a lead insertion lumen. Further, any one of the plurality of lumens of the multi-lumen tube may be used for inserting the thermocouple 27 or may be used for inserting the guide wire G.

(15) In the above embodiment, the case where the ablation catheter of the present invention is applied to a balloon catheter has been described. However, the present invention may be applied to another catheter having a plurality of electrode wires on the outer peripheral side of the catheter body. Good.

(About other inventions extracted from the disclosure scope of this specification)
In the following, inventions that can be extracted in addition to the invention described in the means column for solving the problems within the scope of disclosure of the present specification will be described while showing effects and the like as necessary.

(A-1)
Comprising a tubular catheter body,
The catheter body includes a balloon having an inflating portion that is inflated or deflated using a fluid on a distal end side thereof,
In the ablation catheter in which the electrode wire is provided on the outer peripheral side of the balloon so as to straddle the inflatable portion at least in the axial direction of the balloon,
An annular member provided on at least one of both sides of the inflating portion in the axial direction and disposed so as to surround a part of the outer peripheral surface of the catheter body, and having the electrode wire joined thereto,
The ablation catheter characterized in that the annular member can operate following the displacement of the electrode wire accompanying the expansion of the expansion portion.

According to this configuration, since the annular member can operate following the displacement of the electrode wire accompanying the inflation of the balloon, it is possible to absorb the load applied to the electrode wire during the displacement. As a result, it is possible to suppress inconveniences in which an excessive pulling force is applied to the electrode wire and the electrode wire is disconnected or the inflation of the balloon is inhibited.

(A-2)
The ablation catheter according to (A-1), wherein the annular member elastically deforms following the displacement of the electrode wire accompanying the inflation of the balloon.

(A-3)
The annular member is formed including a coil spring,
The ablation catheter according to (A-2), wherein the coil spring is elastically deformed following the displacement of the electrode wire accompanying the inflation of the balloon.

(A-4)
The ablation catheter according to (A-1), wherein the annular member is capable of moving in the axial direction following the displacement of the electrode wire accompanying the inflation of the balloon.

(B-1)
A tubular catheter body;
An electrode wire provided on the outer peripheral side of the catheter body,
The electrode wire includes a core and an outer layer formed outside the core,
One of the core and the outer layer is made of Ni—Ti, and the other is made of Pt.

For example, in the configuration in which the electrode wire is provided on the outer peripheral surface of the balloon, the electrode wire is displaced (deformed) as the balloon is inflated and pressed against the lesion site, and cauterization with the electrode wire is performed in the pressed state. After the cauterization is completed, the balloon is deflated and the catheter is pulled out of the body. In such a configuration, even when the balloon is in a deflated state, it is assumed that the electrode wire does not return to its original shape from the state of being deformed by the inflation of the balloon, and in that case, when the balloon is pulled out of the body There is a possibility that the electrode wire becomes the resistance of the lead and the operability is lowered. Therefore, in this configuration, in view of this point, the electrode wire is formed by a two-layer structure of Ni—Ti and Pt. In this case, the shape restoration effect of Ni—Ti, which is a superelastic alloy, makes it easy to return the shape of the electrode wire to the original shape when the balloon is in a deflated state. For this reason, when the balloon is pulled out of the body, it can be suppressed that the electrode wire becomes a resistance and the operability is deteriorated.

Moreover, since Pt (platinum) has a contrast function, it is possible to improve the visibility of the electrode lines under X-ray projection. Thereby, the operation | work which arrange | positions an electrode line in a target lesion site | part can be made easy.

(B-2)
The ablation catheter according to (B-1), wherein the core is made of Ni—Ti, and the outer layer is made of Pt.

According to the present invention, since the outer layer made of Pt (platinum) is formed outside the core made of Ni—Ti (nickel titanium alloy), a more preferable configuration can be obtained in terms of cauterization. Further, since Pt is in the outer layer, it is also preferable in terms of contrast.

(C-1)
A tubular catheter body;
An electrode wire provided on the outer peripheral side of the catheter body,
Lead wires are connected to both ends of the electrode wires, respectively, and power is supplied to the electrode wires from the power supply device through the lead wires.

In the configuration in which power is supplied only from one end to the electrode line, it is assumed that the voltage gradually decreases from the one end side toward the other end side in the electrode line. It is assumed that the amount of heat generated from the one end side toward the other end side also decreases. In that case, it may be difficult to cauterize the entire electrode wire at a uniform temperature. According to this point configuration, since electric power can be supplied to the electrode lines from both ends of the electrode lines, the amount of heat generated in the entire electrode lines can be easily made uniform. Therefore, it is possible to make the temperature uniform over the entire electrode line.

DESCRIPTION OF SYMBOLS 10 ... Balloon catheter, 11 ... Catheter tube, 13 ... Balloon, 15 ... Outer tube, 20 ... Electrode wire, 22 ... Annular member, 27 ... Thermocouple, 27a ... Hot junction, 28 ... Insulating tape, 29 ... Cover tube, 30 ... high frequency power supply.

Claims

A tubular catheter body;
In an ablation catheter comprising a plurality of electrode wires provided on the outer peripheral side of the catheter body on the distal end side of the catheter body,
A heat transfer body to which each of the electrode wires is connected;
An ablation catheter comprising: a temperature detection line provided on the heat transfer body and having a temperature detection unit that detects the temperature of the heat transfer body.
The ablation catheter according to claim 1, wherein the heat transfer body is provided along the outer peripheral surface so as to surround the outer peripheral surface of the catheter body.
The plurality of electrode wires are connected to one of an inner peripheral surface side and an outer peripheral surface side of the heat transfer body, and the temperature detection unit is provided on the other side. 2. The ablation catheter according to 2.
The heat transfer body is made of metal,
The temperature detection line is composed of a thermocouple,
The hot junction as the temperature detector in the thermocouple is provided on the other side of the heat transfer body with an insulating layer interposed between the heat transfer body and the heat transfer body. 4. The ablation catheter according to 3.
The ablation catheter according to any one of claims 2 to 4, wherein the plurality of electrode wires are connected to an outer peripheral surface of the heat transfer body.
The said temperature detection part is provided in the state inserted | pinched between the internal peripheral surface of the said heat exchanger, and the outer peripheral surface of the said catheter main body, The Claim 1 thru | or 5 characterized by the above-mentioned. The ablation catheter described.
The heat transfer body is made of metal,
The temperature detection line is composed of a thermocouple,
The hot junction as the temperature detection part in the thermocouple is provided in a state of being covered from the outside by an insulating material on the outer peripheral surface of the catheter body,
The ablation according to claim 6, wherein the heat transfer body is disposed outside the insulating material so that the hot junction is sandwiched between the heat transfer body and the catheter body. catheter.
The outer peripheral surface of the catheter body is covered with a cover tube so as to cover the heat transfer body from the outside,
The ablation catheter according to any one of claims 1 to 7, wherein the cover tube and the catheter body are joined to each other to prevent blood from entering the heat transfer body. .
The catheter body includes a balloon having an inflating portion that is inflated or deflated using a fluid on a distal end side thereof,
The plurality of electrode wires are provided so as to straddle at least the inflatable portion in the axial direction of the balloon on the outer peripheral side of the balloon,
The heat transfer body has an annular shape that surrounds the outer peripheral surface of the catheter body, is provided on either side of the expansion portion in the axial direction, and is joined to one end of the plurality of electrode wires, respectively. Has been
The heat transfer body can be operated following the displacement of the electrode wire accompanying expansion of the expansion part, or the outer periphery of the catheter body on the opposite side of the heat transfer body across the expansion part When an annular member is provided that has an annular shape surrounding the surface and is joined to the other end portions of the plurality of electrode wires, the annular member operates following the displacement of the electrode wires accompanying the expansion of the expansion portion. The ablation catheter according to any one of claims 1 to 8, wherein the ablation catheter is enabled.
One end of each of the plurality of electrode wires is connected to the lead wire via the heat transfer body, and the other end is also connected to the lead wire,
The ablation catheter according to any one of claims 1 to 9, wherein power is supplied to the plurality of electrode wires from the power supply device through the lead wires.